Carbon Nanotube Field Effect Transistors (CNFETs) are excellent candidates for building highly energy-efficient future electronic systems. Unfortunately, carbon nanotubes (CNTs) are subject to substantial inherent imperfections that pose major obstacles to the design of robust and very large-scale CNFET digital systems:
It is nearly impossible to guarantee perfect alignment and positioning of all CNTs. This limitation introduces stray conducting paths, resulting in incorrect circuit functionality.
CNTs can be metallic or semiconducting depending on chirality. Metallic CNTs cause shorts resulting in excessive leakage and incorrect circuit functionality.
A combination of design and processing technique overcomes these challenges by creating robust CNFET digital circuits that are immune to these inherent imperfections. This imperfection-immune design paradigm enables the first experimental demonstration of the carbon
nanotube computer, and, more generally, arbitrary digital systems that can be built using CNFETs. Demonstration of monolithically integrated three-dimensional CNFET circuits will also be discussed.
This research was performed at Stanford University in collaboration with Prof. H.-S. Philip Wong and several Ph.D. students.